Abstract In offshore engineering, the phenomenon of free span often occurs, and pipeline may have multiple spans adjacent to each other, forming a multi-span pipeline. The interaction different makes structural vibration characteristics more complex, which change fatigue affect safety structure. this paper, model tests were designed explore vortex-induced (VIV) pipelines investigate mechanism. ...

Submarine pipeline is a key part in the development of deep sea and ultra-deep oil gas. In order to reduce ovality pipes improve their compressive strength, two-roller continuous calibration (TRCC) process by compression proposed. A springback analysis compress bending carried out, an analytical model established, which predicts after provides theoretical basis for roller shape design parameter...

Abstract Submarine slope instabilities are considered one of the major threats for offshore buried pipelines. This paper presents a novel method to evaluate ultimate pressure acting on pipeline during liquefaction an inclined seabed. Small-scale model tests with pipes at three different embedment ratios have been conducted enhanced centrifugal acceleration condition. A high-speed, high-resoluti...

Large deformation causing damage due to uplift force is generated in buried pipeline located in shallow trenches in marshes and saturated soils. In this paper, existing common methods of pipeline anchorage are discussed and considering advantages and disadvantages of these methods, a new method of pipeline anchorage are studied and presented. In this new developed method, geo-textile materials ...

In submarine oil and gas pipelines, the movement of a differential pressure multisection pipeline robot mainly relies on front rear driving difference fluid friction between cup pipe wall. The passability is key point to guarantee success in scanning detecting inner wall by robot. When moves, force internode connection points changes degree freedom existence causes speed fluctuations during pro...